This invention relates to bushing clamp devices. More particularly, this invention is concerned with an improved electrical bushing clamp for non-metallic sheathed cable.
Many known bushing clamp devices, of the type disclosed in U.S. Pat. No 3,424,856, for example, require the cable to be inserted into the clamp prior to installation of the clamp device in a knock-out aperture. With such clamp devices, the cable is clamped simultaneously with the installation of the bushing clamp in the knock-out aperture. Clamp devices of this type neither allow for the insertion of a cable subsequent to the installation of the clamp in a knock-out aperture, nor for the repositioning of the cable in the clamp device without removal of the clamp from the knock-out aperture.
In another known type of bushing clamp, the cable is clamped by means of a member driven against the cable by a screw or bolt, for example, as disclosed in U.S. Pat. No. 2,973,212. Clamp devices of the type disclosed in Canadian Pat. No. 833,156, for example, employ a clamping member which binds the cable by sliding against it at right angles. While clamp devices of these latter two types do permit the installation of the clamp device in a wiring box prior to insertion of a cable, they do not allow for repositioning a clamped cable without partial disassembly of the clamp device, often requiring the aid of a tool.